Source: https://mochatrade.com/learn/glossary/closing-auction

# Closing auction (official close)
URL: https://mochatrade.com/learn/glossary/closing-auction
Last modified: 2026-10-17

The closing auction is the single matched trade at 1:30 AM IST, 2:30 AM in winter, that sets each US stock's official closing price, about a tenth of the day's volume in one print. Every index and fund is [valued at that close](https://mochatrade.com/learn/us-market-structure/how-us-stock-prices-form), [index funds do their buying in it](https://mochatrade.com/learn/us-market-structure/who-moves-us-stocks), and it is the last real price a [contract that trades overnight](https://mochatrade.com/support/what-is-a-perpetual-contract-and-does-it-expire) can copy until the next open.

## Related terms

- Volume: https://mochatrade.com/learn/glossary/volume
- Opening auction: https://mochatrade.com/learn/glossary/opening-auction
- Overnight session (24-hour stock trading): https://mochatrade.com/learn/glossary/overnight-session
- NASDAQ: https://mochatrade.com/learn/glossary/nasdaq
- Trading halt: https://mochatrade.com/learn/glossary/trading-halt
- Gap up and gap down: https://mochatrade.com/learn/glossary/gap-up-and-gap-down